Ultralow Charge Voltage Triggering Exceptional Post-Charging Antibacterial Capability of Co3O4/MnOOH Nanoneedles for Skin Infection Treatment

The post-charging antibacterial therapy is highly promising for treatment of Gram-negative bacterial wound infections. However, the therapeutic efficacy of the current electrode materials is yet unsatisfactory due to their low charge storage capacity and limited reactive oxygen species (ROS) yields. Herein, the design of MnOOH decorated Co3O4 nanoneedles (MCO) with exceptional post-charging antibacterial effect against Gram-negative bacteria at a low charge voltage and their implementation as a robust antibacterial electrode for skin wound treatment are reported. Taking advantaging of the increased active sites and enhanced OH- adsorption capability, the charge storage capacity and ROS production of the MCO electrode are remarkably boosted. As a result, the MCO electrode after charging at an ultralow voltage of 1.4 V gives a 5.49 log and 5.82 log bacterial reduction in Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) within an incubation time of only 5 min, respectively. More importantly, the antibacterial efficiency of the MCO electrode against multi-drug resistant (MDR) bacteria including Klebsiella pneumoniae (K. pneumoniae) and Acinetobacter baumannii (A. baumannii) also reaches 99.999%. In addition, the MCO electrode exhibits excellent reusability, and the role of extracellular ROS in enhancing post-charging antibacterial activity is also unraveled.

Automated summary

The MnOOH decorated Co3O4 nanoneedles (MCO) design exhibits exceptional post-charging antibacterial effect against Gram-negative bacteria at low charge voltage and can be used as a robust antibacterial electrode for skin wound treatment. The MCO electrode has significantly boosted charge storage capacity and reactive oxygen species (ROS) production due to increased active sites and enhanced OH- adsorption capability. It demonstrates a high antibacterial efficiency against multi-drug resistant (MDR) bacteria, including Klebsiella pneumoniae and Acinetobacter baumannii, with a reduction rate of 99.999%.